Dictionary officials call them "buzzworthy words added to Oxford Dictionaries Online" — "twerk" joins "bitcoin," "selfie," and "girl crush." They'll all now found in the Oxford Dictionaries Online, which is tasked with staying up to date with modern words.

The Oxford Dictionaries Online is one of the largest in the world and adds about 1,000 new entries to its online version every year.

Oxford Dictionaries' spokeswoman Katherine Connor Martin told the Associated Press that "twerking" dates back 20 years, and "the most likely theory is that it is an alteration of work ... with dancers being encouraged to 'work it.' The 't' could be a result of blending with another word such as twist or twitch."

Its sibling publication, the authoritative Oxford English Dictionary, won't be updated with these words anytime soon, unless "twerk, verb" proves to have staying power. Or as the Oxford Dictionaries Online's usage example puts it: "twerk it girl, work it girl."